The present invention relates to a recording medium having, together with video data, sub-picture data stored therein and a reproducing system for the same, and more particularly to a recording medium having video data stored therein which is capable of forcibly reproducing sub-picture in accordance with a state of reproduction and a reproducing system for the same.
Recently, a significant progress has been achieved in developing an optical disk reproducing apparatus adaptable to time-varying images.
The apparatus of the foregoing type is arranged such that data is reproduced from an optical disk which is a recording medium, on which digital data of, images, audio and the like, has been compressed and recorded at a high density and a monitor or a speaker unit is operated in accordance with reproduced digital data. If optical disk reproducing apparatuses of the foregoing type will be mass-produced in the future, a multiplicity of manufacturers are expected to provide a variety of software of motion pictures, those of singing to taped accompaniment and the like.
Hitherto, video tapes have been employed as usual image recording mediums. The video tape having a smaller recording capacity per unit area than that of the optical disk does not permit a complicated random access. Therefore, video data is usually recorded together with audio data such that video data is, as an option, recorded together with single sub-picture data. Audio data and sub-picture data are selectively reproduced by a conventional reproducing system. Since state and time of reproduction of sub-picture data are not controlled, sub-pictures provided for respective scenes cannot be switched.
Video recording mediums having English captions have been widely used in U.S.A. The English caption is recorded on the recording medium as a form of sub-picture data. Then, a system for reproducing the foregoing recording medium selectively turns on or off the English caption. If the English caption is turned off, the reproducing system continuously disables the display of the English caption regardless of a speech expressed by audio data which is reproduced together with sub-picture data.
If a recording medium stores a movie containing a scene in which a speech in a language except for English is expressed, there arises the following problem. If the English caption of the reproducing apparatus is turned off, any English caption is not displayed even in a case where a speech in another language is output. Specifically, a corresponding scene can be considered in which a hero travels from an English language zone to a French language and thus the hero speaks French. If no English caption corresponding to the French speech is displayed, audiences in the English language zone cannot understand the foregoing speech. Similarly, a corresponding scene can be considered in which a hero looks at a label of a medicine written in German. If no English caption indicating the label written in German is displayed, audiences in the English language zone cannot understand the type of the medicine.
The above-mentioned problem can be solved by preparing an additional English caption which is turned on when the main English caption has been turned off and which relates to a speech in a language except for English. In this case, a recording space having a capacity of two times is required to record sub-picture data for the main English caption and sub-picture data for the additional English caption.